Matt Romanowski

Charles, you should be able to tell if the formula changed just by the API spec. If they are different, then you should expect different test results.

Also, I would not suggest 0 weight oil in a Porsche. Remember that all your bearing clearances are based on using a thicker oil. Not to say that the thin oils are not good - there are teams running the Daytona 500 on 5 weight oil!!!! You just have to plan your bearing clearances and oil pump volumes correctly.

Charles Navarro

Well harleys run very hot and can see pretty extreme oil temperatures and I assumed it had to do something with either heat transfer or as an EP additive, which makes more sense since you would have lower oil pressures at extreme temperatures, and would benefit from an additional EP additive, such as boron.

Loaded

FWIW my next oil change will be to Silkolene 15w50 Pro 4 I used silkolene in my drag bike a 1340 cc turbo bike making 325-275h at the rear wheel and NEVER had any failure.

bgiere

Found this VOA (virgin oil analysis) on Valvoline VR1 20w50...it seems as though they have dropped the ZN levels from the last time I saw a VOA on it...

http://theoildrop.server101.com/foru...e=0#Post810397

Charles Navarro

That would go along with my findings from testing Vr-1 20w50. Not to say it is not a good oil - it has one of the highest flash points and shear stability of a non-synthetic out there. I would just throw in some GM EOS or another source to boost the levels up just a tad. There are still many oils with significantly lower levels.

bgiere

Charles, I think you'd be better off with Rotella 5-40 Syn...What are your opinions on that oil for our cars?

Charles Navarro

I would say a syn over a dyno oil any day. Viscosity again depends on what temperature the oil is going to see and how that affect pressure. At bare minimum, 10 psi per 1000 rpm. I would say Rotella syn 5w40 would be a safe alternative to M1 0w40, the latter only being prefered in very low temperatures.

HarryD

Any one have any thoughts on Chevron Delo 400 10W40? Seems to have lots of Zn and P.

Charles Navarro

I would cluster all the 15w40 diesel/mixed fleet oils like delo, delvac, rotella, etc. into the same group. They are all excellent dino oils.

theiceman

you state you would boost with some EOS. How much in a 911 oil cahnge .. a few ounce or a full quart ?


TIA

Charles Navarro

.5 and .66 oz of GM EOS has to be added to each quart of oil to raise the Zn and P by 100 ppm each, which equates to a lot of GM EOS.

It's worth adding that I just got back results of virgin m1 0w40 and it has a little less Zn and P, only about 1100 ppm of each.

bgiere

The VOA on M1 0w40 is interesting...1100 ppm of ZN and P is nice to know. Beats most oils out there today.

Jay H

If I do my math right and assume that a 911 oil system has 12 quarts of oil in it, would it be safe to add somewhere between 6 to 8 oz of GM EOS to an oil change on a 911?

Or am I misinterpreting this info?

Charles Navarro

It's more like 6 to 8 oz to increase the level of Zn and P by 100 ppm each, at a 12 qt fill. This would amount to one bottle per 100 oz roughly (very roughly) per 100 ppm. For example, I would say two bottles of GM EOS would be good to bring Valvoline VR-1 up to the level of Zn and P in m1 15w50 or m1 v-twin 20w50. Now having tested 0w40, I will put in a bottle of EOS at my next fill to bring the level up to that of 15w50.

rllevin

Charles, I have to ask what you think about the Hughes Engines Extreme Pressure Lubricant pointed to in a previously linked article. (The article's here http://www.hughesengines.com/general...icleID=1000039 and the link to the additive is here http://www.hughesengines.com/partDet...p?partID=12697 ). Soluble Moly would seem to answer a lot of concerns about the dwindling Zinc and Phosphorous content in oils not providing sufficient protection against metal to metal contact especially of our cams. Because of its plating protective effect its something I'm interested in adding anyway, as long as it's safe. It might even bring GTX 20-50 back.
Thanks in advance.